Die employed in reclaiming plastic bases of radio tubes



Oct. 28, 1947. J. A. McFARLANE, JR

DIE EMPLOYED IN RECLAIMING PLASTIC BA SES OF RADIO TUBES Filed April 25,1944 Patented Oct. 28, 1947 DIE EMPLOYED IN RECLAIMING PLASTIC BASES OFRADIO TUBES James Albert McFarlane, Jr., Richlands, Va.

Application April 25, 1944, Serial No. 532,666

Claims. 1

This invention relates to a device for reclaiming the plastic bases orplugs used in connection with radio tubes.

Radio tubes as generally manufactured consist of glass or metaltubescontaining the elec trodes and either a vacuum or inert gas, theelectrodes being connected to the exterior by leadin wires and the baseof the glass tube adjacent the lead-in wires bein embraced by a plasticbase provided with a plurality of projecting metal plugs, one for eachlead-in wire.

At present the electrodes are salvaged from the glass tubes but therecovery of the plastic bases with their metal contact plugs has notheretofore been economically possible.

The object of the present invention is to provide a simple device bymeans of which the plastic bases and metal plugs associated therewithcan be economically salvaged.

The invention consists in the novel construction, arrangement andcombination of parts hereinafter more particularly described andclaimed.

One sheet of drawings accompanies this specification as part thereof, inwhich like reference characters indicate like parts throughout.

In the drawings:

Figure 1 shows a perspective view of a tray upon which is mounted aplurality of the improved salvage devices and provided with a masterswitch controlling the operation of all of the thus associated devices;

Figure 2 is a vertical cross-section taken through a single salvage unitillustrated with a radio tube (partially broken away) in position;

Figure 3 is a bottom plan View of a salvage unit showing the electricalconnection to the main circuit of the device of Figure 1;

Figure 4 is a perspective view of a salvage device shown with the bottomup, with a modified form of solder-receiving trough;

Figure 5 is a plan view of one of the contact I members prior toapplication to the device.

In the manufacture of radio tubes the plastic base ordinarily usedcomprises a ferrule F associated with a plastic base B, the plastic basebeing provided with a plurality of outwardly projecting tubular contactmembers 2 usually arranged in a circle and spaced to comate with similarcontact sockets in the radio instrument. In assembling the glass tubewith its enclosed electrodes with the ferrule and base the electricallead-in wires 4-4 which project from the base of the glass or metalradio tube are threaded through the tubular contact members 2 of thebase and their ends are then clipped at the outer ends 3 and secured tothe tubular contact members 2 by small drops of solder which are thenbuffed and provide excellent electrical conduction between theelectrical contact members 2 and the lead-in wires 4. To efficientlysalvage such plastic bases B it is desirable to simultaneously fuse thesmall drops of securing solder 5 from the ends of the lead-in wires 4-4and to this end applicant provides a salvage unit which in the preferredform herein illustrated comprises two spaced base members 1 and 8 ofsuitable material, which base members are provided with a centralkeyhole 9 shaped to accommodate the positioning plug 6 of the radio tubebase B and further provided with a plurality of circumferentially spacedorifices l0 and H in the base members 8 and 1 respectively,corresponding in position with the spacing of the contact members 2 ofthe particular type of radio tube bases to be operated upon. Thecircularly arranged orifices II in the lower base member I arepreferably larger than the corresponding orifices ID in the base member8 for the purpose of receiving resilient heat-conducting members 13 inthe form of split tubular members having an axially extending lug I4 asillustrated in Figure 5. One of these heat-conducting frictional contactmembers is associated with each of the holes H in base member I and thelug I4 is then bent over and back through a radially spaced orifice [2in parallel relationship with the split tubular portion l3, as is wellillustrated in Figure 2. For purposes of assembly it will be noted thatthese heat-conducting members can be arranged in U-form prior to theassembly of the base members 1 and 8 and readily dropped through theassociated orifices l l and I2 of the base member I.

The down-turned lug portions [4 serve to position and hold a circularlyarranged heating coil I6 in close heat-conducting contact with the splittubular portion I 3 and the ends of the heating coil l6 are electricallyconnected as by wires 18 to an electrical circuit l9 arranged in thetray 25 and controlled as by a switch S.

Associated with each of the split tubular heatconducting members I3 is acup-like member l5 which may be welded or otherwise secured to thebottom endof the tubular member or if preferred may be formed integraltherewith as desired. Each of the cup-like members 15 is provided withan inwardly directed lip 21 adapted to maintain in the cup IS apredetermined level of solder. The cups 15 are so positioned withrespect to the tubular members 13 that the bottom ends of the conductorplugs 2 of the radio tube will be submerged in the solder held by thecups and thus rapidly fused to free the conductor wires 4 from saidconductor plugs 2. As accretions of solder form in the cups I5 the levelwill be maintained substantially constant by means of overflow throughthe lips 27.

A modified form of solder maintaining cup is illustrated in Figure 4,illustrated as a ring-like member [5' formed with circumferentiallyspaced lips 22 and outwardly extending lugs 2| by means of which it canbe associated with the base members l and 8 in the assembly of thelatter as by means of rivets H. The base members 7 and 8 are furtherprovided in opposite corners with aligned holes [9 adapted to receivescrews 26 to attach each unit to the top 24 of a tray 25 as illustratedin Figure 1 by means of which a plurality of such salvage elements canbe operated as a unit. The top 24 of the tray will be provided with aplurality of spaced holes 23 adapted to receive the salvage units.

In operation and with the salvage units constructed as previouslydescribed and assembled on a tray as illustrated in Figure 1, theoperator will position in each salvage unit a radio tube T, the currentbeing turned on to the circuit 59 through switch S and thereby heatingthe heating element I6 of each of the salvage units. A few secondssufiice to unsolder the contacts between the lead-in wires 4 and theradio tube contact plugs 2 so that the operator can lift the radio tubeT from the base B with the lead-in wires intact, leaving the plasticbase B also intact with its associated metallic plugs 2. It will beunderstood that any cementitious material associating the glass portionof the tube with the ferrule F and base B will be previously softened bya suitable solvent.

Various modifications in the precise construction and arrangement of theparts will readily suggest themselves to those skilled in the art butwithin the scope of the present invention as claimed.

Having thus described my invention, I claim:

1. Device for reclaiming bases of radio tubes comprising a base havingorifices spaced to receive the contact plugs of a radio tube, means ineach orifice for receiving and frictionally gripping the plug therein,and means for applying solder fusing heat to the ends only of saidplugs.

2. Device for reclaiming bases of radio tubes comprising means forreceiving and holding the contact plugs of the radio tube, means forapplying solder fusing heat to the ends of said plugs, means formaintaining pools of molten solder with which the ends only of the plugswill contact, and means for directing the overflow from said pools tomaintain a substantially constant level therein.

3. Device for reclaiming the bases of radio tubes comprising a baseprovided with a plurality of orifices arranged in groups, the orificesof each group arranged to comate and receive the contact plugs of aradio tube, means spaced below each orifice adapted to hold a portion ofmolten solder at a fixed level, a heating conductor surrounding andadjacent the solder holding means of each group and means for supplyingheating current to said heating conductors.

4. Device for reclaiming bases of radio tubes comprising a base having aplurality of orifices arranged in groups, the orifices of each grouparranged and spaced to conform with that of the contact plugs of theradio tubes to be handled, friction means in each orifice adapted toengage and position a contact plug, means positioned below each orificeto hold a deposit of solder at a substantially constant level below eachcontact plug and means for applying heat to said solder holding means tomake said solder deposits molten.

5. In a device for reclaiming bases of radio tubes, a base having aplurality of spaced chambers, a removable cover for each chamber, eachof said covers formed of superposed parts provided with a plurality ofthrough aligned orifices arranged and spaced to correspond with andreceive the contacts of a radio tube, the lower of said cover partsprovided with additional orifices adjacent the first mentioned, frictioncontact members each having a split tubular portion with an axiallyextending lug of sufiicient length to be bent back substantiallyparallel with the tubular portion with said lug and tubular portionseated in adjacent orifices in said lower part, means for securing thecover parts together with the frictional contact members positioned inthe orifices, a heat conductor coil passing between and frictionallyengaging the lugs and tubular parts and means carried by said lowermembers to receive heat from said coil and support a portion of solderat a predetermined level below the cover substantially as specified.

JAS. ALBERT MCFARLANE, J R.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,600,675 Kaye Sept. 21, 19261,780,778 MacFadden Nov. 4, 1930 1,792,434 Lockwood Feb. 10, 19311,963,794 Kimbell June 19, 1934 2,293,455 Disch et a1 Aug, 18, 19422,312,181 Matthews Feb. 23, 1943

